TWO plants known as Nepeta septemcrenata (N.S.) and Otostegia fruticosa (O.F.) of family Lamiaceae were chosen for the present study. The volatile oils (V. oil) of aerial parts of both plants were isolated by hydrodistillation method and their constituents were identified using GC/MS analysis. It was found that nepetalactone (53.65%) and caryophylline oxide (60.86%) are the main components in both N.S. and O.F., respectively. The lipid constituents were extracted with pet. ether and fractionated to fatty alcohols, unsaponifiable materials and fatty acids which were identified by GLC analyses. The antimicrobial activity of different extracts of both plants (V. oil, pet. Ether, Fatty alc., Fatty acids (F. acids), 70% methanol, Chloroform and Ethyl acetate)were evaluated using disc diffusion method against gram positive and gram negative bacteria in addition to fungi. The results proved that, the V. oil and ethyl acetate extract of N.S. are the most effective on E. coli, while, the F. acids fraction and 70% alc. extract of O.F. exhibited the highest activity against Staphylococcus aurous and Asparaglus niger , respectively